10 replies to this topic

[JohnDoe999]

http://jonbarron.org...may-harm-vision

 

 

I refer to this article which claims that a certain form of glaucoma can be caused by drinking more than 3 cups of coffee each day.

 

I have some problems with understanding the logic in this particular statement:

 

"Decaffeinated coffee, as well as other sources of caffeine including soda, tea, and chocolate, were not determined to have any link to the development of exfoliation glaucoma"

 

As far as I know, decaffeinated coffee is just regular coffee with the caffeine removed, so in reality this should mean that it is just the caffeine, and nothing more, that causes this form of glaucoma.

 

However, the article further states that it is ok to drink other beverages with caffeine. I.e. then it is reasonable to assume that it is not the caffeine that is causing the glaucoma. 

 

What am I missing?

 

Should I conclude that it is caffeine, but only in an amount over 3 cups of coffee (300 mg?) that causes the problems? Should we then also conclude that pure caffeiene pills also can cause this kind of glaucoma (over 3 pills)?

[nightlight]

 

What am I missing?

 

This is merely a weak statistical correlation (RR=1.66) on non-randomized samples (i.e. scientists didn't randomly assign half the subjects and have them drink 3+ cups of coffee/day, and the rest of subject as controls not drinking coffee).

 

All such association shows is that habit X="drinking of 3+ cups of caffeinated coffee" is in the same web of causes and effects as disease D="exfoliating glaucoma" but not what is the nature of the links.  Such association is not equivalent to statement S="X causes D". At the level of association RR=1.66 there may be thousands of other nodes in the same web of causes and effects. Usually when RR is 3 or more, one may take such observation as a hint of causal relation between X and D. But even then one needs hard science (experiments, randomized trials, etc) to uncover the nature of the links observed on non-randomize samples.

[JohnDoe999]

Thanks for your answer!

 

I see that this article, based on various research, postulates that it is not caffeine, but some of the other substance in coffee that increases IOP:

 

http://www.cverges.c...f-glaucoma..htm

 

I also read another article some days ago, don't remember the link right now, which found that energy drinks actually lowered IOP, and the postulation was that is was caffeine in interaction with taurine which lowered IOP

 

Which, for practical issues related to myself, as so far indicates that I should skip coffee altogether, and instead take caffeine pills or energy drinks until I am able to go off caffeine completely.

 

[JohnDoe999]

Here is link showing that direct application of pure caffeine to the eye did NOT elevate IOP. 

 

http://www.ncbi.nlm....pubmed/22140308

 

and this is the research showing that energy drinks LOWERS IOP:

 

http://www.dovepress...ed-article-OPTO

 

I.e. it should be safe to consume any other caffeine infused product but coffee and decaffeinated coffee

[Kalliste]

Coffee has received some considerable attention in the recent years. Some very positive studies have been done independent from each other. It has serious chemopreventative effects, powerful protection from the metabolic syndrome and some neuroprotective effects, i.e it inhibits Alzheimers. This taken togheter with the flaws in this study means I'm happily going to down 2-3 cups a day. I intend to expand the number as I grow older and my endogenous antioxidants are lowered.

Edited by Cosmicalstorm, 19 November 2014 - 03:04 PM.

[JohnDoe999]

I would also happily continue to drink 2-3 cups a day, since I am familiar with all the results pointing at other positive health effects, but since I have experienced increased IOP without any apparent reason, and the so called "Eye specialist" only tells me to come back again in one year, I have to take the issue in my own hands, so to speak. By the way, I have also found research showing that all of my allergy medications can increase IOP, i.e. the allergy tablets, the allergy nasal spray, and the allergy eye drops. The "specialist" did not ask me any question other than if any other in my family had IOP.

 

Back to the coffee, however. As cited above, some research states that it is not caffeine, but some of the other substances in coffee, that can increase IOP. Caffeine injected directly in the eye did not increase IOP. Some research also states that taurine combined with caffeine (i.e. most "energy" drinks) lowers IOP.

 

Could one therefore postulate as follows: One cup of coffee can increase IOP with x percent. Taurine combined with caffeine can decrease IOP with y percent. I.e. if I drink a cup of coffee each day, and combine this with a 500 mg Taurine capsule before the coffee, then I would experience an increase in IOP, theoretically, of (X - Y), or experience an decrease in IOP, theoretically, of (Y+X), or maintain IOP equilibrium if X=Y ?

[niner]

I would also happily continue to drink 2-3 cups a day, since I am familiar with all the results pointing at other positive health effects, but since I have experienced increased IOP without any apparent reason, and the so called "Eye specialist" only tells me to come back again in one year, I have to take the issue in my own hands, so to speak. By the way, I have also found research showing that all of my allergy medications can increase IOP, i.e. the allergy tablets, the allergy nasal spray, and the allergy eye drops. The "specialist" did not ask me any question other than if any other in my family had IOP.

 

I had high IOP for a number of years, but it wasn't high enough to medicate, just high enough to follow on a yearly basis.  You are probably in that range, but there's something you can do for it-- laser iridotomy.  When my ophthalmologist retired and I went to a newer guy, I learned that laser iridotomy is now considered the standard of care for my condition.  I got a tiny hole punched in my iris with a laser in a painless procedure that might have taken 30 seconds per eye.  Problem solved.  The pressure can now equalize, and it was covered by insurance.  (Not much help if you aren't insured.)   Is your guy an MD?

 

I'm not interested in giving up coffee.

[JohnDoe999]

 

I would also happily continue to drink 2-3 cups a day, since I am familiar with all the results pointing at other positive health effects, but since I have experienced increased IOP without any apparent reason, and the so called "Eye specialist" only tells me to come back again in one year, I have to take the issue in my own hands, so to speak. By the way, I have also found research showing that all of my allergy medications can increase IOP, i.e. the allergy tablets, the allergy nasal spray, and the allergy eye drops. The "specialist" did not ask me any question other than if any other in my family had IOP.

 

I had high IOP for a number of years, but it wasn't high enough to medicate, just high enough to follow on a yearly basis.  You are probably in that range, but there's something you can do for it-- laser iridotomy.  When my ophthalmologist retired and I went to a newer guy, I learned that laser iridotomy is now considered the standard of care for my condition.  I got a tiny hole punched in my iris with a laser in a painless procedure that might have taken 30 seconds per eye.  Problem solved.  The pressure can now equalize, and it was covered by insurance.  (Not much help if you aren't insured.)   Is your guy an MD?

 

I'm not interested in giving up coffee.

 

 

Neither am I, really. I love coffee. The guy is an MD, that is correct; with a specialization on top in eye health. Thanks for your tip. I shall check if this procedure is covered in our country. What was you IOP before you got this procedure, and what is it now?

[niner]

I don't remember exactly what my IOP was- it was somewhere in the high teens/low twenties before the iridotomy, and, um, "lower" afterward.  (something that was considered normal or at least safe)

 

BTW, I don't make much of the weak association in this paper, for the reasons that nightlight pointed out.   FWIW, there are reports in the literature of certain herbal extracts (Pycnogenol, and I think Bilberry, but don't quote me on it) can reduce IOP.  Pycnogenol didn't do much for me in that regard, although it's useful for other things. 

[jakebvt]

Not really related but my eye twitches when I drink too much coffee.

 

One morning I took 5 cups before an exam. I ended up getting a panic attack during the exam and nearly failed. Oops.

 

My doctor told me to stop drinking coffee but I still do sometimes. It messes up sleep rhythms even when only taken during the morning. I switched to powdered caffeine but it doesn't really make much of a difference either consumption method.

[Mind]

Some past discussions on coffee:

 

http://www.longecity...r-brain-health/

 

http://www.longecity...e-and-lifespan/

 

http://www.longecity...-for-longevity/

 

http://www.longecity...c/45138-coffee/

 

I started drinking coffee about 6-7 years ago. Will continue due to the weight of epidemiological evidence being quite positive for it's consumption.